Characterisation, modelling and assessment of native vegetation condition in Tasmania

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1 Characterisation, modelling and assessment of native vegetation condition in Tasmania Who: Grant Dickins & Karyl Michaels, Project 1, University of Tasmania & RMIT University Team Members: Prof. Tony Norton, Prof. Simon Jones, Dr Gang-Jun Liu, Dr Karyl Michaels, Dr Michael Lacey, Grant Dickins, James Shaddick, Liz Farmer PhD Scholars: Grant Dickins, Karen Eyles, Kathryn Sheffield, Alex Lechner, Naoko Miura, David Henderson

2 The ESCAVI proposed that the approach to assessing the condition of native vegetation should: Use a common conceptual basis (agreed frame of reference) BENCHMARKS Use a consistent and quantified approach in acquiring information on the condition of native vegetation

3 State approaches to native vegetation condition assessment Victoria: Habitat Hectares Tasmania: TASVEG VCA New South Wales: Biometric Queensland: BioCondition South Australia: Bushland Condition Monitoring (BCM) Northern Territory: under development West Australia: under development

4 Components measured for forest tree canopy cover and health vegetation patch size & connectivity (neighbourhood & core area) large old trees and canopy health recruitment of woody species logs understorey life forms diversity and cover organic litter lack of weeds

5 Components measured for non- forest vegetation patch size & connectivity (neighbourhood & core area) dominant life form cover Understorey life forms diversity and cover organic litter persistence potential lack of weeds

6 Building a systematic national approach to NVC assessment and monitoring Assessment methods Habitat Hectares, Biometric, Vegetation Condition Assessment Issues site-based measures have a limited temporal history minimal temporal impacts long term monitoring capability overall a lack of site data to inform models for what purpose are vegetation assessments being done characterisation, monitoring, management of vegetation extent, conservation, etc cost and seasonality of remotely sensed imagery lack of supportive frameworks to support research Landscape Logic (P1) hosted a national workshop in 2007 to discuss and draw together the technical approaches to help set a new national research agenda

7 What others are doing in Australia Andre Zerger et al. scaling up site based measures to landscape level using predictive modelling Graeme Newell et al. spatially modelling vegetation condition using multiple site assessments and supportive datasets Richard Thackway (VAST) vegetation information to report on condition, status, type, extent, assessing options, prioritising investment, monitoring to achieve targets, etc Landscape Logic Native Vegetation Condition Framework - PhD (Grant) Landscape Metrics (Karyl, Michael & Tony)

8 Fragstats 25m grid analysis of non-agricultural land with native vegetation Vegetation patches >50m apart are considered to be separate patches Patches may contain multiple vegetation types Output provides a good indication of vegetation fragmentation across Tasmania

9 Landscape Metrics Identify the largest and/or most ecologically significant remnant patches first Characterising patches defined by: spatial metrics (patch size, connectivity) conservation/reservation status priority habitat for threatened species Outcomes by catchment there may be n priority patches that benefit from further vegetation modelling

10 Towards an Integrated Framework for the Assessment and Monitoring of NVC: a case study from Tasmania Rubicon Catchment Grant Dickins, PhD Project grant.dickins@rmit.edu.au

11 Research Aims Apply condition modelling capabilities and techniques analysis of existing site survey data (VCA/HH methods and core variables) perform simulated condition modelling and comparative analysis of assessment methods Develop framework for NVC research provide roadmap for other research and applications opportunity to strengthen long term assessment and monitoring efforts in Tasmania

12 Research Steps Selection of core vegetation indicator variables determine core attributes appropriate for indicating vegetation condition ~ i.e. which deliver 90% of info what variables are readily collected and applicable to other landscapes Informed and complemented by Landscape Metrics apply thesis model to significant patches identified through Landscape Metrics project Future linkages application as preferred tool/method tie into research networks, TERN

13 Methods used to generate climate surfaces Climate surface coefficient files Climate surfaces Bioclimatic parameters Elevation Slope Aspect DEM

14 Bioclimatic Parameters Bioclimatic parameters are based on climate variables (max. and min. temperature, rainfall, solar radiation and pan evaporation), used as surrogates to approximate energy and water balances at a given location, and useful in determining the climatic envelope for plant and animal species 35 Bioclimatic parameters have been derived from mean monthly or weekly climate estimates of max. and min. temperature, rainfall, radiation, evaporation, and a digital elevation model

15 Bioclimatic Parameters

16 P28. Annual Mean Moisture Index The mean of all weekly moisture index values The weekly moisture index values are calculated from the weekly precipitation and evaporation values in conjunction with the soil type and maximum soil water availability values you supply The water balance model used to compute the moisture index mimics the effects of precipitation and evaporation: for each week in turn it adds water to the soil from precipitation (up to the limits imposed by the soil characteristics), and takes it away by means of evaporation

17 Remote Sensing Native Vegetation Condition S. Jones, K. Sheffield, N. Miura, A. Lechner

18 Ground Sampling Protocol Ikonos MS 3 x 3 pixel cluster (12m x 12m) Ikonos MS 5 x 5pixel cluster (20m x 20m) Site spatial extent (70 m x 70m) SPOT 5 MS 3 x 3 pixel cluster (30m x 30m) SPOT 5 MS 5 x 5 pixel cluster (50m x 50m) Second plot assessment Plot assessment includes a 20m x 50m plot and a 50m transect GPS point 20m x 20m quadrat, located in the centre of the plot First plot assessment Plot assessment includes a 20m x 50m plot, 20m x 20m quadrat and a 50m transect Site boundary Site is 130m x 130m 20m x 50m plot 50m transect, located through the centre of the plot

19 Remote Sensing in Landscape Ecology: scale and accuracy effects on characterisation of landscape pattern, linear features, patch size, and length & grid position on the probability of feature extraction The position of a satellite sensor array s grid is random with respect to features in the landscape. An example of 3 different possible positions of the grid out of an infinite number of possibilities A discrete linear strip has been broken up into smaller patches as a result of the relationship between the feature s position and dimensions and the grid position Alex Lechner, PhD Project a.lechner@student.rmit.edu.au

20 LIDAR for Vegetation Condition Surveys Continuous waveform vs. discrete return systems Pulse emission nanosec % 100% meters 0 6 LIDAR systems can acquire multiple measurements from a single laser pulse first return no return % 100% LIDAR data represent direct measurements of three-dimensional vegetation structure second return third return fourth return % 100% 50% 100% 50% 100% % 100% 42 Courtesy Optec Inc

21 Plan Range Intensity Classification

22 Summary Multiple research questions and technologies being employed A better perception of the state and resource condition of native vegetation in Tasmania Developing and demonstrating a scientifically credible framework for assessing and monitoring NVC in Tasmania Contributing to a nationally consistent approach to NVC and native vegetation management

23 Workshop - Integrating vegetation condition mapping into regional conservation assessment and planning How can vegetation condition mapping be used for improved management of biodiversity? What are the key challenges in integrating vegetation condition mapping into regional conservation assessment and planning? What are NRM management needs and expectations for mapping vegetation condition at different scales?